Investigating the Effects of Altering Portion Size Reduction Awareness on Compensatory Eating Behaviour

Sponsor

University of Liverpool (Other)

Overall Status

Recruiting

CT.gov ID

NCT06119295

Collaborator

(none)

108

Enrollment

Location

Arms

Anticipated Duration (Months)

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The present study aims to investigate whether energy intake is reduced when participants consume a reduced portion size (15% compared to the 'control' portion), and also to see whether awareness of this reduction affects energy intake.

Condition or Disease	Intervention/Treatment	Phase
Eating Behavior Obesity	Behavioral: Portion size manipulation	N/A

Detailed Description

In the present study, all participants will participate in two sessions - the baseline session and the experimental session. In the baseline session, participants will be given ad libitum access to a lunch meal (followed by ad libitum access to dessert), and ad libitum access to a dinner meal (followed by ad libitum access to dessert). Then, after a washout period of between 1-6 weeks, participants will return to complete the experimental session, where they will be randomised to one of three conditions:

Condition 1 (control condition): The same as the baseline condition except that the lunch will be of a fixed portion which participants must consume all of - this portion size will be the same amount of food as was consumed in the ad libitum lunch meal in the baseline session (participants will be told that the amount of food served is the same as the amount they consumed in the baseline session).

Condition 2 (reduced aware condition): The same as the baseline condition except that the lunch will be of a fixed portion which participants must consume all of - this portion size will be 15% less than the amount of food consumed in the ad libitum lunch meal in the baseline session (participants will be told that the amount of food served has been reduced from the amount they consumed in the baseline session).

Condition 3 (reduced unaware condition): The same as the baseline condition except that the lunch will be of a fixed portion which participants must consume all of - this portion size will be 15% less than the amount of food consumed in the ad libitum lunch meal in the baseline session (participants will be told that the amount of food served is the same as the amount they consumed in the baseline session).

Study Design

Study Type:

Interventional

Anticipated Enrollment :

108 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

None (Open Label)

Primary Purpose:

Treatment

Official Title:

Investigating the Effects of Altering Portion Size Reduction Awareness on Compensatory Eating Behaviour

Anticipated Study Start Date :

Oct 30, 2023

Anticipated Primary Completion Date :

Apr 30, 2024

Anticipated Study Completion Date :

Apr 30, 2024

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Control Condition Participants will be served a lunch - this will be of a fixed portion - this portion size will be the same amount of food as was consumed in the ad libitum lunch meal in the baseline session (participants will be told that the amount of food served is the same as the amount they consumed in the baseline session).	Behavioral: Portion size manipulation The intervention will be administered via changing portion sizes of foods served to participants. Depending on the condition participants are in, they will be served either a portion size which consists of the amount of food they consumed in the first test session, or a reduced portion size. Within these two reduced portion size conditions, one group of participants will be made aware that their portion size has been reduced, the other will not and instead will be told that this portion size is the same as the amount of food they consumed in the previous session.
Experimental: Reduce aware condition Participants will be served a lunch - this will be of a fixed portion - this portion size will be 15% less than the amount of food consumed in the ad libitum lunch meal in the baseline session (participants will be told that the amount of food served has been reduced from the amount they consumed in the baseline session).	Behavioral: Portion size manipulation The intervention will be administered via changing portion sizes of foods served to participants. Depending on the condition participants are in, they will be served either a portion size which consists of the amount of food they consumed in the first test session, or a reduced portion size. Within these two reduced portion size conditions, one group of participants will be made aware that their portion size has been reduced, the other will not and instead will be told that this portion size is the same as the amount of food they consumed in the previous session.
Experimental: Reduced unaware condition Participants will be served a lunch - this will be of a fixed portion - this portion size will be 15% less than the amount of food consumed in the ad libitum lunch meal in the baseline session (participants will be told that the amount of food served is the same as the amount they consumed in the baseline session).	Behavioral: Portion size manipulation The intervention will be administered via changing portion sizes of foods served to participants. Depending on the condition participants are in, they will be served either a portion size which consists of the amount of food they consumed in the first test session, or a reduced portion size. Within these two reduced portion size conditions, one group of participants will be made aware that their portion size has been reduced, the other will not and instead will be told that this portion size is the same as the amount of food they consumed in the previous session.

Arm

Intervention/Treatment

Experimental: Control Condition

Participants will be served a lunch - this will be of a fixed portion - this portion size will be the same amount of food as was consumed in the ad libitum lunch meal in the baseline session (participants will be told that the amount of food served is the same as the amount they consumed in the baseline session).

Behavioral: Portion size manipulation

The intervention will be administered via changing portion sizes of foods served to participants. Depending on the condition participants are in, they will be served either a portion size which consists of the amount of food they consumed in the first test session, or a reduced portion size. Within these two reduced portion size conditions, one group of participants will be made aware that their portion size has been reduced, the other will not and instead will be told that this portion size is the same as the amount of food they consumed in the previous session.

Experimental: Reduce aware condition

Participants will be served a lunch - this will be of a fixed portion - this portion size will be 15% less than the amount of food consumed in the ad libitum lunch meal in the baseline session (participants will be told that the amount of food served has been reduced from the amount they consumed in the baseline session).

Behavioral: Portion size manipulation

Experimental: Reduced unaware condition

Participants will be served a lunch - this will be of a fixed portion - this portion size will be 15% less than the amount of food consumed in the ad libitum lunch meal in the baseline session (participants will be told that the amount of food served is the same as the amount they consumed in the baseline session).

Behavioral: Portion size manipulation

Outcome Measures

Primary Outcome Measures

Immediate energy intake post-fixed lunch meal [Within 30 minutes after intervention administered]
Amount of energy consumed from the lunch dessert
Total delayed post-fixed lunch meal energy intake [Within 10 hours after intervention administered]
Amount of energy consumed from the post-lunch snack box intake, dinner meal, dinner dessert, post-dinner snack box intake, additional energy intake
Total post-fixed lunch meal energy intake [Within 10 hours after intervention administered]
Amount of energy consumed from the lunch dessert, post-lunch snack box intake, dinner meal, dinner dessert, post-dinner snack box intake, additional energy intake

Secondary Outcome Measures

Post-lunch snack box intake [Within 4 hours after intervention administered]
Amount of energy consumed from snack box consumed between lunch and dinner
Total intake of the ad libitum dinner meal [Within 4-5 hours after intervention administered]
Amount of energy consumed from the dinner meal

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 60 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

United Kingdom (UK) residents able to visit laboratory on campus in Liverpool, aged ≥ 18
Body Mass Index (BMI) between 18.5 and 32.5 kg/m2
Proficiency in English language
Self-report willingness to eat each of the test foods

Exclusion Criteria:

Current medication use which affects appetite
Pregnant
Currently or previously diagnosed with an eating disorder
Currently on a diet
Have any food allergies or intolerances
Are vegan

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	University of Liverpool	Liverpool		United Kingdom	L69 7ZA

Sponsors and Collaborators

University of Liverpool

Investigators

None specified.

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

Responsible Party:

University of Liverpool

ClinicalTrials.gov Identifier:

NCT06119295

Other Study ID Numbers:

Portion size reduction study

First Posted:

Nov 7, 2023

Last Update Posted:

Nov 9, 2023

Last Verified:

Nov 1, 2023

Individual Participant Data (IPD) Sharing Statement:

Yes

Plan to Share IPD:

Yes

Studies a U.S. FDA-regulated Drug Product:

Studies a U.S. FDA-regulated Device Product:

Study Results

No Results Posted as of Nov 9, 2023